Overtraining is a topic of enormous popularity, both among ‘bros’ (ala “You have to wait a week after training a bodypart, to let it recover.”) and in the evidence-based community (just look to the past three years of continuous discussion of Maximum Recoverable volume). Unfortunately, it remains poorly understood, both in terms of the mechanisms which underlie it, and in terms of what it actually is in practice. Now, given I lack the technical knowledge to offer a substantial discussion of those mechanisms, I’d like to lay out what I’ve found to be some of the most common and clear indicators of overtraining, with the goal of making it less of a theoretical concept, and more of a phenomenon one can readily identify in practice.

WHY OVERTRAINING MATTERS

Before digging into that, though, I’d like to briefly argue for the fact that misunderstanding overtraining doesn’t fulfill the stereotype of the mere technical problem with minimal, if any, practical implications; it can have real, negative practical implications, in the form of impaired progress on the one hand, and perpetual overtraining on the other.

For example, imagine the case of a relatively new lifter, who has only ever been exposed to material which claims it takes a muscle a full week to recover after being trained, and that if one exceeds this training frequency, they’ll overtrain. If said lifter really believes this (and there’s no clear reason for them not to, as the claim is intuitively plausible, and they’ve not been exposed to any other ideas), they’ll leave gains on the table by not using a higher training frequency. Indeed, given the strength of the literature on the superiority of training a muscle two or more times a week versus once a week, the degree to which their progress will be limited will likely be quite significant.

Similarly, someone under the impression that overtraining is very easy to cause might be systematically overly conservative in their training, perhaps using insufficiently heavy loads, staying too far away from failure, and not performing enough volume – and, again, make slower progress than they could (or even no progress!).

On the other hand, the absolute workhorse trainee might take to heart the idea there is no such thing as overtraining (or that overtraining is exceedingly rare, or that it’s actually caused by undereating) and thus train themselves into the ground. Even worse, by not really believing in overtraining, they might be confused and frustrated by this experience (because, well, it can’t be overtraining!), and respond by simply working harder – making this overtrained state self-sustaining and thus a perpetual problem.

In short, it’s clearly an imperative we develop a proper practical understanding of overtraining – both to ensure optimal progress, and, well, quite literally to avoid having to experience overtraining on a remotely regular basis. To that end, here are some major symptoms to look for (note that this list is semi-comprehensive, in that I wrote about everything which struck me as a good example, but I don’t mean to claim these are the only symptoms of overtraining one can experience):

SYMPTOM 1: MENTAL FATIGUE

This might seem an odd place to start, but I think understanding the way in which overtraining can affect you mentally is valuable precisely because it’s less obvious than physical symptoms.

Fundamentally, it needs to be understood that overtraining is a systemic, or whole-body, problem. As such, while exercise is, of course, a primarily physical activity, the symptoms of true overtraining are not constrained to physical symptoms, such as feeling tired. Indeed, it’s been my experience the mental symptoms of overtraining are often the most apparent and frustrating!

Specifically, overtraining tends to cause a vague, incessant ‘brain fog’, which can interfere with cognition across the board. Thus, when suffering from mental fatigue of this kind, you might experience uncharacteristic inattentiveness, a lack of mental drive or motivation, poor recall, and a tendency to make small technical errors you typically wouldn’t. Interestingly, things like frequent, minor spelling mistakes and struggling to remember words seem to be unusually good ‘tells’ of the presence of mental fatigue, as is the general feeling of simply being less intelligent, or slower in your thinking, than usual.

To be sure, different people will display overtraining in different ways, and will even display particular symptoms in different ways. As such, some overtrained persons might not experience mental fatigue at all (although I think this is unlikely), some will display a particular set of mental symptoms (say, lack of motivation more than anything; I address this at greater length at the end of this piece), and others will display, well, others (for example, impaired verbal fluency in particular). However, my experience has been that mental fatigue, if present, is sufficiently obvious to not be something you have to try to discern; if it’s there, it’s readily apparent.

In short, profoundly fatiguing the body through consistent and excessive exercise will fatigue the mind. Thus, if you find yourself just not ‘feeling yourself’ mentally, I encourage you to not automatically write that off as unrelated to your training, especially if other symptoms of overtraining are occuring at the same time.

SYMPTOM 2: CONSTANT, EXAGGERATED PHYSICAL FATIGUE

Alright, so this one is about as obvious as it’s going to get: mechanism notwithstanding, overtraining – real overtraining – generates profound physical fatigue. Now, because physical fatigue is generally a non-pathological process intended to encourage rest and recuperation when bodily resources are relatively depleted, it’s important to differentiate between that normal, healthy, non-pathological tiredness – inherent to life – and the fatigue generated by overtraining. Fatigue-driven overtraining, rather than being a reflection of normal living (for example, feeling tired after a hard workout is to be expected, and doesn’t necessarily indicate anything beyond the fact you just had a hard workout), is constant (or near-constant) and disproportionate to the immediate context. In other words, overtraining makes you exhausted at baseline, and anything requiring physical effort is more difficult and tiring than it should be.

In my experience, one of the best indicators of overtraining-induced fatigue is feeling dead tired upon awakening, even after sleep of appropriate length and quality. In my mind, you couldn’t ask for a more straightforward indication that something is wrong, and, medical conditions notwithstanding, this is one of the biggest red flags for overtraining – especially if it’s consistent across multiple days.

SYMPTOM 3: SLEEP DISTURBANCES

Sleep is arguably the greatest contributor to recovery (if you’re interested in testing this, try training when well-rested but underfed versus sleep-deprived but well-fed; I bet the rested condition will win). Thus, it’s highly intuitive that when your recovery demands consistently exceed your recovery capacity, sleep changes can result.

Most obvious is simply increased sleep duration. For example, I vividly recall one lifter telling me that when he got a job which required him to walk hours a day (which was in addition to his near-daily lifting sessions), he suddenly required ten hours of sleep a night to feel rested. Particularly telling, though, is the fact sleep, in its totality, tends to be subjectively less restful when you’re overtrained – even if you’re getting more of it! In my mind, this speaks to increased recovery demands in a broad sense (creating a requirement for more sleep), as well as an unusually severe stress response (resulting in diminished sleep quality).

This is borne out in practice, as we do see sleep disturbances in those who are overtrained. In particular, delayed sleep onset (literally taking longer to get to sleep; technically different to insomnia) and early morning awakening (waking earlier than usual, without intending to; trust me when I say this is not a good thing, as it usually results in sleep deprivation). Of course, sleep disturbances are tough to pin down, as they can be caused by a wide range of medical conditions, and they can also be idiopathic, or primary, conditions (which is to say they’re not attributable to other, more fundamental problems). However, if you’re someone who doesn’t usually suffer from these issues, and you suddenly find yourself struggling with them alongside one or more of the other symptoms listed here, or you normally struggle with sleep disturbances but find them exacerbated, overtraining might be the culprit.

SYMPTOM 4: CHANGES IN HUNGER & APPETITE

To properly contextualize the discussion of these symptoms, I’d like to take a moment to describe the distinction between hunger and appetite, as it’s one which can have important practical implications.

Technically, hunger is the physical sensation, or discomfort, caused by needing to eat . On the other hand, appetite is the desire to eat. In other words, while hunger is the predominantly physical drive to eat, appetite is the predominantly psychological drive to eat. Fortunately, the levels of hunger and appetite we experience are usually roughly equivalent, such that when we feel hungry, we also have an appetite.

Unfortunately, overtraining can cause significant changes to both hunger and appetite. Specifically, both hunger and appetite tend to either increase considerably (which makes sense: you’ve chronically exceeded your recovery capacity, so your body is, presumably, encouraging the consumption of additional nutrients to drive recovery), or decrease (which also makes sense, as stress reduces hunger and appetite in some people). Fascinatingly, these changes in hunger and appetite can occur independently of one another, ultimately resulting in levels of hunger and appetite being significantly different. Beyond being annoying, this mismatch can cause negative behavioral changes, such as massive overeating driven by elevated appetite, itself caused by stress, or undereating, despite elevated hunger, as a result of appetite being suppressed by stress.

Thus, eating behavior tends to be all over the place in the context of overtraining, with some people struggling not to eat everything in sight, and others finding food unusually uninteresting. In either case, it’s important to base your actual food consumption on an objective assessment of what you believe to be physically and psychologically ideal, rather than ‘going by feel’ in a context in which that ‘feel’ may be unreliable.

SYMPTOM 5: REDUCED SEX DRIVE

Although the biological purpose of life is reproduction, it’s important to keep in mind the truism that you need to be alive to reproduce. As such, when a stressor is imposed on you, the relative importance of reproductive drive is reduced in favor of dealing with the stressor .

Anecdotally, it’s apparent that overtraining can be a strong enough stressor to generate this effect. Admittedly, it’s been my experience that changes in sex drive when overtrained are less common than, say, chronic mental fatigue, which means an absenceof change in sex drive doesn’t reasonably lead to the conclusion you’re not overtrained. Instead, consider this a possible rather than probable symptom, and be particularly cognizant of it being combined with other symptoms.

SYMPTOM 6: REDUCED PUMPS

This is simultaneously one of the coolest symptoms of overtraining and one of the least intuitive, and a prime example of something I long left in the category of “I don’t know why this happens, but it happens!” Amusingly, after mere seconds of thinking about this while writing this article, it occured to me there’s a very straightforward explanation for it: cortisol, the best-known and most significant of stress-related hormones, is a vasoconstrictor , which is to say it causes blood vessels to narrow. In lay terms, increased stress corresponds with increased cortisol production, which creates a higher concentration of cortisol in the blood, which causes greater vasoconstriction, which causes impaired pumps (given pumps are mediated by vasodilation – widening/relaxation of blood vessels).

In practice, my experience has been that this is a surprisingly reliable indicator of overtraining, so if you notice worse pumps despite unchanged diet, hydration, and preworkout supplementation (as all of these can influence muscle fullness and blood flow during exercise; even plain old caffeine acts as a vasodilator in skeletal muscle during exercise), this may be a red flag for overtraining. I’d note that if you notice this symptom in the absence of more obvious/significant symptoms like physical fatigue, you might simply be unusually stressed rather than overtrained (this is something I’ve experienced repeatedly).

SYMPTOM 7: REDUCED DESIRE OR MOTIVATION TO TRAIN

(Be forewarned: this section ended up more technical than I originally intended, but I think it’s purposeful, and if you stay with me, you’ll see where it leads.)

Highly relevant to this section is the concept of psychological reinforcement. If you’re unfamiliar with it, here’s a primer:

Reinforcement, in the broadest sense, is any consequence of a behavior which influences the probability of that behavior occurring again. For example, if you go to the mall, and while there something happens which makes you more, or less, likely to go to the mall again, that event would quality as a form of reinforcement.

More specifically, positive reinforcement is a response to, or result of, a behavior which increases the likelihood of that behavior being repeated . For example, if when you work hard on a school paper you receive a good grade, getting that good grade can reinforce the general behavior of working hard on school papers.

On the other hand, negative reinforcement is a response to, or result of, a behavior which decreases the likelihood of that behavior being repeated. To parallel the previous example, if when you don’t work hard on a school paper you receive a bad grade, that consequence can decrease the likelihood you’ll fail to work hard on school papers in the future.

So how does this relate to overtraining? Well, in normal circumstances exercise is positively reinforced, both in the short term (by making you feel better), and in the long term (by causing positive health and body composition changes). However, when overtrained, this reinforcement tends to become negative: workouts which would normally make you feel energized simply wipe you out, and you become progressively more worn down one day to the next (assuming you don’t alter your training). Eventually (and by “eventually”, I mean in as little as a few days), this can create an association between training and feeling worse, which, reasonably, decreases your desire to train.

It’s important to keep in mind that all of this, although unpleasant, is a fundamentally healthy response to overtraining, in that it encourages precisely the thing that will allow you to return to a non-overtrained state: rest. As such, it is an imperative this not be confused with normal malaise, which you really might be better off training through. In other words, this is a prime example of a context in which  ‘listening to your body’ isappropriate, as the feedback it’s given you is reliable.

PUTTING IT ALL TOGETHER

In this article, I’ve laid out seven common symptoms of overtraining. This naturally leads to a question: how many of these symptoms need one have to reasonably conclude they’re overtrained?

At the risk of giving a non-definitive answer, I think this is an area in which each of us needs to use our own best judgment, rather than holding to a hard and fast rule. I say this because there simply isn’t a hard and fast rule upon which one can rely across contexts. For example, someone suffering from severe physical fatigue, despite appropriate diet and sleep habits, etc, and not having any relevant medical conditions, may well be overtrained, even if their cognition, hunger, appetite, and sex drive are unaffected. In other words, that single symptom, lacking a better explanation, might be sufficient to indicate overtraining. In other instances, however, one might need to simultaneously experience multiple symptoms to be confident in concluding overtraining, given each of these symptoms can arise for other reasons.

Fortunately, from a practical perspective, these symptoms do tend to cluster. For example, as previously discussed, physical and mental fatigue tend to come hand in hand; this is highly intuitive, as it’s difficult to imagine being physically exhausted and concurrently totally clear-headed (after all, the mind is dependent on the brain, and the brain is part of the body). As such, while I don’t want to just fall back on some variation of “It’s obvious, bro!”, the truth is overtraining is obvious in most cases, if you know what to look for.

Although this might be a topic more fundamentally suited to its own article, I think it’s important to end with this message: more often than not, the real issue relating to overtraining – at least for experienced, consistent, serious trainees – is the tendency to want to keep training hard even when they’ve already overdone it. Trust me, I’ve learned this lesson the hard way many times myself (and I’m far from being an elite lifter!). So remember: while knowledge is power, power, not used, doesn’t help you.

 Admittedly, even this conception of hunger is an oversimplification, as it doesn’t account for the possibility of incongruences existing between hunger and the level of food consumption which is actually physiologically necessary. These incongruences can be caused by anything from sleep deprivation to drug use to leptin resistance, and can be highly problematic when food intake isn’t directly controlled. However, this simplified definition definitely suffices in this context.

 Again, an oversimplification, but which should suffice in this context.

 Technically, the presence of cortisol increases the vasoconstricting effects of epinephrine and norepinephrine, yielding an indirect vasoconstricting effect.

 Technically, it’s possible for positive reinforcement to fail to actually influence the likelihood of the relevant behavior being repeated. For example, if someone does something good, and they’re offered money as a reward, but they don’t perceive this money as being valuable, the positive reinforcement of offering them money isn’t actuallyreinforcing of anything. However, it’s arguably still appropriate to call it “positive reinforcement”, as the intention of the monetary reward is to reinforce the relevant behavior.